Consistent naming "Briar" throughout app
The following discussion from !274 should be addressed:
- [ ] @ialokim started a [discussion](https://code.briarproject.org/briar/briar-desktop/-/merge_requests/274#note_73755): (+3 comments)
> While trying out the installer generated by the CI, I noticed we use "Briar" as the application name during installation and also for the `.desktop` file for Linux, but the title of the main window is "Briar Desktop". Not sure if we should instead be consistent.
TL;DR: We probably want to use "Briar" everywhere instead of "Briar Desktop".
issue